1. Field of the Invention
The invention pertains to blow molding machines, and in particular, to an adapter interposed between an expansible chamber motor and a blow pin permitting relative radial adjustment of the blow pin and expansible chamber motor piston to accurately position the blow pin with respect to shear steels and air seal adjacent the machine mold.
2. Description of the Related Art
The blow pin of blow molding machines is supported by and advanced and retracted with respect to its associated mold by an expansible chamber motor. The inner or lower end of the blow pin is located within the mold in which the blown product is shaped, and the inner end cooperates with the air seals and also functions as an anvil which forces the plastic against the shear steels to shear the neck of the blown article, such as a synthetic plastic beverage bottle, when the blow pin is raised. The shear steels are mounted upon top blocks and in order for the shear steels to properly correlate to the blow pin inner end, the blow pin must be accurately located relative to the top blocks and shear steels.
Due to misalignment in the blow molding machine head, inaccuracies in the blow pin configuration, or for other reasons, it is difficult to maintain the accurate dimensional tolerances necessary between the location of the blow pin inner end and the shear steels to achieve optimum shearing.
Previously, a quick accurate system for positioning the blow pin and the adjacent shear steels has not been available wherein adjustment could be quickly accomplished by a machinist of ordinary skill.